I don’t know about you, but we don’t use buttermilk very much. If I would buy buttermilk it would go bad before I could use it all and I hate wasting anything. So, if you are like me then you will love that all you need is regular milk and either lemon juice or white vinegar (I use vinegar). When a recipe calls for buttermilk and you don’t have any on hand or choose not to buy it.
Buttermilk Substitute (Sour Milk)
Use the same amount of sour milk as buttermilk. For every one cup of milk, place one tablespoon of lemon juice or vinegar in a glass measuring cup.
Put your tablespoon of vinegar or lemon juice in the measuring cup first, then add enough milk to make the desired amount the recipe calls for.
Let stand 5 minutes.
Example: Put 1.5 tablespoons of vinegar in the glass measuring cup then pour enough milk to make 1.5 cups sour milk (buttermilk)